1. The Field of the Invention
The present invention relates to systems and methods for searching a data store. More particularly, the present invention relates to systems and methods for focusing or scoping a search of the data store by restricting the search results of a query to a particular subset of the search results.
2. The Prior State of the Art
One of the advantages provided by computers is the ability to electronically store information. This information often takes the form of spreadsheets, documents, electronic messages, and databases. Storing information electronically is advantageous for many different reasons. Changes to the stored information can be made quickly and easily by multiple users and the stored information can frequently be electronically sent to another person.
Businesses, home computers, Internet sites and other computer systems all maintain stores of data. These data stores can be specific to a particular type of data or can be a general repository for data. An example of a data store that is specific to a type of data is a mail store, which is primarily used to store electronic messages. In fact, a mail store is a component of practically every computer system. The mail store is highly compartmentalized, and can store a large amount of data. Usually, each user of the computer system is assigned a mailbox in the mail store and the user can store electronic messages in their portion of the mail store and it is not uncommon for each user to store large numbers of electronic messages.
Another significant advantage of storing information or data electronically is the ability to electronically search the information. The ability of a user to search data stores is facilitated by programs that index those data stores. When a user submits a search query, the index assists a user in identifying and locating data or documents that may interest the user. More specifically, the content index for a data store can quickly identify those documents that match a particular search query. The data structures of the content index are highly compact and are inexpensively accessed.
For example, a mail store can contain a significant amount of data in the form of electronic messages and for that reason, the mail store is often indexed to facilitate a search of the mail store for specific electronic messages. Currently, an index of the mail store will allow various messages within the mail store to be identified or located when a user specifies one or more search terms. However, many of the messages identified and located by the search are not contained in the mailbox of the user performing the search. Messages that are not located in the user's mailbox are not useful to the user primarily because the user does not have permission to access those messages. For that reason, the user performing the search is interested only in the messages that are in the user's mailbox. A significant disadvantage of current search techniques is that extra processing time is required to identify which messages in the search results are located in the user's mailbox. This is particularly true when a server computer is indexing the content on behalf of the user.
For example, when a user is searching the mail store, the content index cannot currently account for the fact that the user is usually only interested in messages that are in that user's mailbox. When the user specifies a certain search query, the content index identifies all messages within the mail store that satisfy the search query. These search results must be reduced to those that are specific to the user's mailbox. This is accomplished by accessing the property store for each of the messages identified from the content index to determine which mailbox or folder contains the messages. In other words, the content index does not index mailbox information, which must be retrieved from another source such as the property store. The mailbox information retrieved from the property store is compared against the user's mailbox information and only those messages that are in the user's mailbox or folder are returned in the search results. This process can consume significant processing time because there may be a large number of messages identified by the content index and because the property store is accessed randomly. The property store is randomly accessed because the messages identified by the content index are in no particular order with regard to the mail store. More specifically, the content index does not index or group the mail store according to individual mailboxes.
In other words, the ability to scope or focus a search is currently implemented by filtering the results obtained from the content index against the Uniform Resource Locator (URL) retrieved from the property store for each result. Only those documents whose URL matches the URL of the scope restriction (the user's mailbox) are ultimately returned to the user. As previously indicated, the process of filtering the results against information in the property store can take a long time, especially because the property store is randomly accessed.